In this project, amorphous calcium phosphate (ACP), an important intermediate in the formation of apatite, is being investigated for possible use as a dental material. When either used alone, or in combination with other dental materials, especially polymeric resins, ACP has a wide range of possible applications such as in restorative composites, cavity liners and bases, luting and pulp capping agents, prophylactic and endodontic sealants, and as a component in periodontic packs and impression pastes. It has a number of potential advantages over other calcium phosphates for these purposes. As a dental cement, its advantage over current biphasic systems (e.g., dicalcium/tetracalcium phosphate mixtures) is its simpler, single solid phase formulation. When included as a component in appropriate resin-based composites, sealants and adhesives, ACP may be useful as a remineralization agent as well as a vehicle for sustained, controlled release of inorganic anticaries ions such as fluoride. Currently, chemical studies on various ACP-resin formulations are being carried out to examine ACP's potential as a remineralization agent. Results to date indicate that discs of ACP- embedded, methacrylate resins release calcium and phosphate ions at levels that exceed the thermodynamic minimum necessary for remineralizing damaged tooth surfaces.